Steam-heating system



Dec. 18, 1928. "1,696,028

| w. CARROLL STEAM HEATING SYSTEM v Original Filed Jan. 1925 2 Sheets-Sheet 1 .Zizv nimc L OLZIS W Car/0f] Dec. 18, 1928.

L. w. CARROLL STEAM HEATING SYSTEM Origina1.Filed Jan. 1925 2 Sheets-Sheet 2 hatenteel Dec. "1.8,

nirsn srares LOUIS w. cnnnonn, or nrvnnsrnn, rnnrnorsQAssrsivonor ONE-HALF 'MUFFLY, OF CHICAGO, ILLINOIS. v

eeann Parana; OFFMIE.

r0 GLENN STEAM-HEATING sYsrnM.

Original applicationfileglianuary 3, 1925, Serial no} 406. Divided and this application filed December 23,

1926. Serial No. 156,680.

This invention relates to improvement's'in heating systems of the low pressure type, such as are employed for heating buildings, and the like, and is a division of 'application'for patent Serial No. 106, filed January 3,1925, on steam heating system.

The main objects ofthis invention are" to provide an improved furnace adaptable for closely regulatedheating systems; to provide improved means for controlling the combustion and the water feed in a low pressure furnace; to provideimproved means for regulating thewater level in an open feed water tankln proportion to'the vapor pressure in the furnace so that a constant water level is maintained in the boilerunder the varying vapor pressures; to provide the improved means for indicating the pressure in the boiler; to provide an improved safety relief; to provide improved means for indicating the boiler water level; to provide improved means for controlling the combustion thru a wide range; and to provide a, sensitive con trol operated by the vapor pressure for simul taneously controlling the feed water and-the furnace combustion. I 1

A11 illustrative embodiment of this inven} tion is shown in the accompanying drawings, in which: 7 I I Fig. 1 is a generalview of asystem embodying the improvements provided in my invention as installedin a building. f 1 Fig.2 is a vertical sectional View of the furnace, showingthe boiler feed and damper control features of this invention.

Fig. 3 is a section taken on the line 3- 3.

of Fig. 2. I I u Fig. 4; shows the upperend of the boiler with parts thereofin a changed position.

Referring to the drawings, the furnace 1 includes a combustion ch mber 2 having grates 3, and a boiler or vaporizing space 4:. The exhaust flue 5 leads out from the upper end oi the combustion chamber 2 and a by pass flue 6 is connected to the ashpit 7, below the 'rates 3, and joined into theexhaust pipe 5 fo r 'ward of the hinged damper 8.

I The vapor from the water space 1 passes out through the pipe line 9. which taps into the riser'pipe '10, connected into the upper end of the water space 41. The pipe 9 leads throughout the building and distributes the heated vapor to the various radiators 11. In

the system shown .a return pi in 18 is ro- LI 7 I I I g; I

vided for the radiators, and the condensed vapor flowsback and discharges from the spill Din i i a certain amount oi water is lost through into the feed water tank 15. Since leakage in the circulating system, or evaporation from the feed water tank, provision is made for automatically adding a compensating amount of water from the water line 16, which has an outlet 17 over the feed water tank.

Figures 2, 3 and 4 illustrate the method of obtaining a very sensitive and positive regulation of combustion in response to small vak viding'a very sensitive draft and feed water control.

Tn the form shown the controlling instru- 'men'tality'comprises a manometer which may be a float or a bell 18, which is open at the bottom, and is suitably guided for free ver-- tical movement within an open water tank 19. The. bottom of the tank 19 is provided with an inwardly projecting portion 20, which extends into the bell 1 8, and to the upper end of which is connected the riser pipe 10 from the waterspace 4, which also serves to support the tank. Thevapor or vapor pressure is admitted into the bell18, and in passing around the outer edges condenses and provides awater'seal, The-height'o'f the water is governed by the height of the inner projection 20, since the water o'verflows'over the top of the projection 20 and runs'back into I the boiler. The pressure in the boiler, us ual- 'l a few ounces causes a difference in'the Q 7 water levels lnside andoutside of the bell, and the area of the bell provides sufliclent power from the low unit pressure to operate the damper and feed water control. I

Upward pressure on the bell 18, in excess of atmosphericpressure, rotates the lever 22 counter-cloclnvise. The lever 22 1s fulcru'med I at the bracket 23, secured to the wall of the tank 19, and is connected .by means of a pivoted link 241 to the upper end of the float 18. On the opposite side of the fulcrum 23, the lever is connected by means of the rod 25 to the end of crank arm 26' jl'hedamper tical travel.

' pressure.

shaft 27, which is rotatably mounted in the flue pipe 5.

In the raised or vertical position shown in 2, the damper 8 is vertical and obstructs the passage in 5, closes the air inlet orifice 28 in the rear of the bypass flue 5, and opens the flue 6 to the exhaust flue 5. tectually dampens the combustion on the grates 3, and the air which leaks into the ashpit is by-passed directly into the exhaust pipe.

In the lower position of the float 18, the damper 8 is positioned as shown in Fig. 4. In this position the exhaust flue 5 is unobstructed, and the by-pass pipe 6 is completely closed to the flue 5. Also, the aperture 28is open to theatmosphere and supplies fresh air to the grates 3 through. the ashpit 7. These two positions provide for a zero draft and a maximum draft on the fire, and the intermediate positions of the damper will regulate the combustion draft to any desired. de

y gree between. A very slight fluctuation of the vapor pressure is suiiiclent to move the damper through the full arc or ninety degrees. The manifest differences between this method of draft regulation and those in common use are that the mechanical parts are well balanced, and that resistance to the movement of the float 18 is practically constant for a considerable distance in its ver- Euch is not the case with the usual flexible pressure actuated diaphragms which provide for very little movement and offer a widely varying resistance to the fluid By rotating the damper instead of lifting it, a large amount of the friction usually encountered, especially from the chains and cables which are arranged to operate over pulleys for the operation of such dampers is eliminated. Inthis invention the resistance of the damper movement is reduced suf iciently so that it becomes practical to operate the dampers directly from the very low vapor pressures without introducing a secondary source of power. The amount of water in the open receptacle 19 is self-regulating, as explained above, and the diilerences in the water levelswill be only a few inches. A common working pressure for a vapor heating system of this type is about four ounces per square inch, This produces a difference of about seven inches between the water levels. No additional safety valve is required in tl s arrangement, as the water seal provides a very positive acting sartety valve. The height of the drum 19 establishes a maximum steam pressure at which steam will escape through the water seal, and this pressure cannot be changed by the operator or by accidental means. I

The products of combustion are drawn out from the passage 5, through the fines 29, which extend through the feed water tank 15 and connect into the chimney or stack at 30. This arrangement serves to utilize the heat of This position eh.

:01? the bell crank lever 87.

the exhaust gases for raising the temperature of the feed water in the tank 15. The preheating of the returned water by the flue gases andthe sensitive control ofthe steam pressure inthe boiler are important features of the complete system, which is designed especially for use in connection with the combination steam and water radiatorsshown herein, and more fully described in my '00- pending application, Serial No. 406, dated January 3, 1925.

The returned water is spilled from the pipe 1 1 into the open feed water tank 15. This also allows any air in the return system 18 to escape. The tank 15 is connected from a point near the upper part oi the tank to the lower portion of the water chamber 4 by means of the open pipe 31. Thus, the level of the water in the tank 15 is slightly higher than the level or" the water in the boiler, which is under the pressure of the vapor. The water level in. the tank 15 may be used as a guide for determining when additional water should be added to the system, thus saving the cost of the usual water gage andeliminating the danger of broken gage glasses.

By providing a float 32 for controlling the outlet valve 83, in the end of the pipe 17, water is automatically added whenever the level falls below a predetermined point. This makes the replenishing of water completely automatic.

Since the bell 18 moves in response to a very small difference in pressure, it prevents anexcessive steam pressure and also eliminatesthe customary steam gage. Gradua tions placed upon a stationary sector. 3%, mounted on the tank 19, will indicate by the position of the pointed end 35 of the lever 22 the steam pressure more accurately than. is shown by the usual low pressure steam gages.

To improve the steaming qualities of the furnace and to keep a constant water level in the boiler, an interconnection between the rod 25 and the mechanism of the feed water float 32 is arranged toccmpensate for the varations in steam pressure, and thus provldes a still more accurate control over the supply water to the system. A pin 36 on the rod 25 engages in the forked end of one arm The lever 37 is pivoted at 38 to a fixed bracket 89, attached to the pipe 17. The downwardly extending arm of the bell crank lever carries the pivot pin 40 of the float lever 41.

irregularly camshaped surface 'sL3,[bearing agalnst the lower end of the stem of the sup- "ply valve 88. When therod 25 is stationary,

V The rearwardly extending end 1-2 of the float lever 41 has anthe difierence between the water levels in the feed water tankand the boileris at a maxias described.

said means for varying the 'water level in a lower level of water.

mum, since the vapor pressure in the boiler is at the highest point. WVhen the steam pressure falls and the bell 18 moves down to the lowest position, the rod 25, having the pin 36, is raised and moves the float pivot 40 nearer to the stem of the valve 33. This changes the leverage of the float 32 on the valve 33, and also the shape of the cam surface 43 will allow the valve 33 to close at It is evident that when the water in the tank 15 is replenished during a period of low pressure in the boiler,

the level in the feed water tank should be lower than if replenished during a high pressure. The ratios of the lever and the contour of the surface 43 are so designed that a practically uniform volume of water is maintained in the system, whether the boiler is cold or under full pressure.

I At a given steam pressure in the boiler, the level in the tank 15 will be at a given height above the boiler water level. Hence, the gage 43, rigidly attached to the float 32 and coacting with the pointer provided by the inner end of the lever 37, will indicate very closely the water level in the boiler and replace the customary water gages.

practically constant steam pressure, there being only a slight difference between the-maximum and minimum allowable pressures, but there are differences in the boiler level and feed water tank level at the slightly diflerent,

boiler pressures. This difl'erence in level for indicating purposes is substantially com-. p'ensated for by attaching the pointer to the between said arm and the valve for regulatbell cranklever 37 and the gage to the float,

closed steam and water space, an open feed water tank connected to said space,,means for supplying water to the tank and means operated by the pressure in the space to controlthe feed water tank as the vapor pressure in the said space varies so as to maintain a constant water level in said space at diflerent vapor pressures. i

2. In combination, a furnace having a closed steam and water space, an open feed water tank connected to said space, and means controlled by the vapor pressure in said space for varying the height of the water in said tank to maintain the Water level in said space constant at differentvapor pressures therein. r

The heating system is designed to operate with a 4. In combination in a furnace having a closed water vaporizing space, a feed water tank connected with said space, a fixedly. mounted valve for controlling the water supply to said tank, a pivotally mounted bell crank having a depending arm, a float pivoted on said arm and engaging with the valve, and means actuated by vapor pressure in the said space for positioningv the bell crank to regulate theaction of the float upon said valve. I 5. In combination in a device of the class described, an open feed water tank, a bell crankhaving a pivot in fixed relation with the tank, said crank having a depending arm, a float pivotally mounted on said arm, a fixed water supply pipe having a valve controlled by the float, and means for positioning the bell crank to govern the relation between the float pivot and said valve to change the water level at which the float will close the valve.

6. In a device of the class described, a boiler, an open feed water tank communicating therewith, an inlet valve for the tank, a

means sensitive to pressure in said boiler for moving the said pivot to change the relation ing the water level in the tank at which the i float will close the valve.

7. In combination, a vaporizer having a combustion chamber provided witha grate in the bottom and a closed water vaporizing space around the combustion chamber; an outlet flue leading from the upper end of the combustion chamber; a by-pass flue leadingv from underneath the grate to said flue; an air inlet to the by-pass flue; a centrally pivoted damper for simultaneously controlling the outlet flue, the by-pass flue and said air inlet, in proper relation for controlling theamount of air drawn through the grate; and a float actuated by the vapor pressure in the water space for controlling said damper.

Signed at Barcelona this 7th day of July,

LOUIS W. CARROLL. 

